Power supply designers seek to design power converters that are stable. While power supply designers prepare models and check frequency response from these models for designed power converter circuitry to confirm stability, such models do not account for all the potential disturbances in the system and can be error prone. As a result, power supply designers prefer to measure the frequency response of the power supply circuit to verify the modeling, and ensure stability of the power supply circuit. Additionally, for power stages whose model can be complex to calculate, a black box approach based on just the frequency response measurement can be used to verify stability of the system.
The figures are not to scale. Wherever possible, the same reference numbers will be used throughout the drawing(s) and accompanying written description to refer to the same or like parts.